[media] as102: add __packed attribute to structs defined inside packed structs

This patch fixes a regression in kernel 3.3 due to this patch:

http://patchwork.linuxtv.org/patch/8332/



That patch changes "#pragma pack(1)" with "__packed" attributes, but it is not
complete. In fact, in the as102 driver there are a lot of structs/unions
defined inside other structs/unions.
When the "__packed" attribute is applied only on the external struct, it will
not affect the internal struct definitions.
So the regression is fixed by specifiying the "__packed" attribute also on the
internal structs.

This patch should go into 3.3, as it fixes a regression introduced in the new
kernel version.

Signed-off-by: Gianluca Gennari <gennarone@gmail.com>
Signed-off-by: Ryley Angus <rangus@student.unimelb.edu.au>
Cc: stable@kernel.org # for v3.3
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>